Maintaining the Perl 5 Core: March 2017 report

This is a monthly report by Dave Mitchell on his grant under [Perl 5 Core Maintenance Fund](http://www.perlfoundation.org/perl_5_core_maintenance_fund). We thank the TPF sponsors to make this grant possible.

The main things I did last month were:
* working on fuzzer-related tickets in the security queue;
* working on tickets in the 5.26 blocker queue;
* investigating the possibility of storing short strings directly in the
head of an SV, eliminating the need for an SV body or malloced string
buffer. The short conclusion was that it probably wont work robustly.
* reducing the size of my p5p mailbox, which had grown to 14,000 emails
over the years. It's now down to a few hundred. This was achieved firstly
by simply deleting any threads more than 3 years old, then
reading/processing/deleting any threads/tickets newer than that.
SUMMARY:
0:30 "do 'file.pl'" warnings
2:53 RT ##131083 Bleadperl breaks App-PDF-Link-0.18
0:15 RT #130841 AddressSanitizer: heap-buffer-overflow
2:38 RT #130841 heap-buffer-overflow in Perl_newSVpvn_flags
1:18 RT #130861 AddressSanitizer: heap-use-after-free in Perl_pp_rv2sv
11:52 RT #130915 AddressSanitizer: heap-buffer-overflow in Perl_do_vecget
2:39 RT #130916 heap-buffer-overflow in S_ckwarn_common
0:33 RT #130918 heap-buffer-overflow in Perl_pad_free
2:42 RT #130921 BBC re-engine-GNU-0.021
1:18 RT #130934 heap-use-after-free in Perl_yyparse
0:44 RT #130981 Confusing B::Deparse output with unless/elsif
0:44 RT #131033 t/op/range.t fails
1:53 RT #32714 Objects destroyed in the wrong order during global destruction
1:30 fix build warnings and smoke failures
17:31 investigate short-string PVs
31:12 process p5p mailbox
1:04 revert base.pm @INC changes
4:57 review blocker tickets
6:01 review security tickets
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92:14 TOTAL (HH::MM)
180.7 weeks
2549.0 total hours
14.1 average hours per week
There are 251 hours left on the grant